5 U.S.C. § 503
- (a)For the purpose of this section, “agency” has the meaning given it by section 5721 of this title.
- (b)A witness is entitled to the fees and allowances allowed by statute for witnesses in the courts of the United States when—
- (1)he is subpenaed under section 304(a) of this title; or
- (2)he is subpenaed to and appears at a hearing before an agency authorized by law to hold hearings and subpena witnesses to attend the hearings.